As incorporation of fluorine into organic molecules is becoming a pharma fad, we are getting more interest in 19F NMR experiments. The biggest practical problem is how to get a 13C spectrum of a fluorinated compound without using a very large sample concentration. I would like to have a way to 19F decouple during the 13C FID, but then I would lose the 1H decoupling. I'm wondering how people are dealing with this problem, if there are any interesting experiments or methods. Of course, hardware is always a limitation. Bruker said they could modify our 400 probe to "widen" the 1H coil to include 19F, with a small sacrifice of 1H sensitivity. One method I can imagine is to record two 13C spectra: one 19F deoupled and one 1H decoupled, and then combine the data somehow.
I just got a quote from Bruker for a 19F probe for our 600, the price was about 2X what I expected for a typical probe. I'm wondering what people consider the price of a 600 MHz single-axis gradient probe to be these days.
Any suggestions or anecdotes will be appreciated.
Neil
Received on Tue Nov 10 2015 - 09:52:23 MST